Hello. My name is***** can help you with your question.
The Z323 speakers have their own power supply, so make sure that is plugged in directly to the wall outlet. If you have done this and the problem continues, then the most likely problem is that the speakers are defective. If you purchased them recently I would exchange them with your retailer. If not that they are still under warranty, let me know and I can provide you the information to get them fixed or replaced under warranty.
It will still be under warranty. Just contact the warranty department at +1(###) ###-####to arrange the warranty repair or replacement.